A frail Ethel Kennedy showed up at the Westchester County courthouse this morning to support her daughter Kerry Kennedy on the first day of her trial on drugged driving charges.

Ethel Kennedy, the 85-year-old widow of Sen. Robert F. Kennedy, was in a wheelchair and accompanied by an unidentified man and woman when she entered the courtroom shortly after 9 a.m.

Kerry Kennedy had hoped to avoid a trial, but her bid to have the case tossed failed last week after a judge denied her motion to have the case dropped because she supposedly took a sleeping pill by accident.

Even if Kennedy – the ex-wife of Gov. Andrew Cuomo – accidentally drugged herself with a sleeping pill, she broke the law if she kept driving after feeling the effects, prosecutors had argued.

Kennedy’s defense team had argued that since prosecutors admit they have no evidence that she intentionally took the sleeping pill Zolpidem instead of thyroid medicine that the charges should be dropped.

Kennedy, 54, was charged with drugged driving in 2012 after her car hit a tractor trailer on a highway in Westchester.

During jury selection, Acting Supreme Court Justice Robert Neary did not allow defense lawyers to ask potential jurors about their political affiliations, but said they can ask if they have any “strong feelings” about the Kennedy family.

In addition to character witnesses, the defense plans to call a Massachusetts pharmacologist, Dr. David Benjamin.

The prosecution’s witness list includes Elizabeth Stratton as an expert in Zolpidem.

Kennedy is also expected to testify.

Meanwhile, Robert F. “Bobby’’ Kennedy Jr., 60, asked for compassion for his misunderstood sister, a lawyer and professional human-rights activist.

“Kerry’s been instrumental in freeing political prisoners and dissidents from around the globe from imprisonment and torture,” Bobby told The Post’s Andrea Peyser.

He argued that political agitators all over the world could be locked up and tortured if his sister is convicted in Westchester County for being hell on wheels.